Core-former



Feb. 24,1970 T. NAYAGAM f 3,497,174

CORE-FORMER Filed Feb.'23. 1967 5 Sheets-Sheet 1 Www/sy Feb. 24, 1970 T. NAYAGAM 3,497,174

CORE-FORMER Filed Feb. 25, 1967 3 Sheets-Sheet 2 ZwE/y To Q 77mm ,WA/wrm MMM 1770 zA/Ey Fa. 24, 1970 1-.NAYAGAM 3,497,114

conm-roma Filed Feb. 2s. 1967 s sheets-sheet 3 United States Patent O 3,497,174 `CORE-FORMER Tharma Nayagam, Petaling Jaya, Selangor, Malaysia, assignor to Madame Suzanne Nayagam, nee Perrin, Petaling Jaya, Selangor, Malaysia Filed Feb. 23, 1967, Ser. No. 618,089 Claims priority, application Switzerland, Mar. 4, 1966, 3,170/66 Int. Cl. B28b 7/30 U-S. Cl. 249-180 2 Claims ABSTRACT F THE DISCLOSURE The present invention has for object a core former to form a passage in a construction element of hardening material, said core former comprising two channelshaped elements turned down one on the other with their edges facing each other, with means for separating or bringing together these two shaped elements in the shuttering or dismantling position, and sealing means to close the free space between the longitudinal edges of the shaped elements in the shuttering position.

Such core formers are known which make use in particular of a tubular element formed of a steel sheet having a longitudinal slot closed by a removable rubber joint. During shuttering of a passage in a concrete element, this packing is placed in the joint to prevent the concrete from penetrating into the tubular element and to hold apart the two longitudinal edges of this element. During dismantling the rubber joint is withdrawn, which permits of exibly closing the tubular element so as to be able to withdraw it from the hardened concrete. The life of such a core former is limited because it cannot practically be employed more than 500 times. Furthermore, the tubular element being llexible, it is necessary to hold it by outer means to prevent it from warping under the action of the fresh concrete.

The laying of the rubber joint demands rather complicated and delicate work before positioning the core former for the shuttering. The fact that this core former is to be withdrawn after each use limits the weight and consequently the dimensions of the tubular element. It is not possible to produce large sections of passages in view of its relatively low resistance to the presure of the concrete.

The present invention aims at overcoming these disadvantages and the core former which is'the object thereof comprises two channel-shaped elements turned down one on the other with their edges facing each other, means for separating or bringing together these two shaped elements `one from the other in the shuttering or dismantling position and sealing means to close the free space between the longitudinal edges of the shaped elements in the shuttering position.

The accompanying drawing shows, by way of example, one embodiment of the core former object of the present invention.

FIGS. 1 and 2 are cross sections of this core former in two different positions.

FIGS. 3 and 4 are views similar to FIGS. 2 and l respectively in onelapplication of the core former.

FIG. 5 is an end view of this same core former.

FIG. 6 is a partial view in side elevation on a smaller scale and partly in axial section of the core former.

FIG. 7 is a view of a detail of this core former.

FIG. 8 is a diagrammatic view on a still smaller scale of the complete core former.

FIG. 9 is an end view of a construction element produced by means of ve core formers such as the one shown in FIG. 8.

FIGS. l0 and 1l are sectional views of a variant of a detail of FIGS. 1 and 2, in two different positions.

FIGS. l2 and 13 are views in side elevation of two variants of FIG. 7.

The core former shown in FIGS. l to 8 serves to form a passage C in a construction element E of concrete such as shown in FIG. 9. It comprises two channel-shaped elements 1 and 2. These two elements 1 and 2 are turned down one on the other with their edges 3, 4 and 5, 6 respectively facing each other. Each edge is rolled over itself inwardly of the shaped element so as to form supports 3', 4 and 5', 6" respectively.

The shaped element 1 has on the inside cross ribs 7 regularly spaced along the shaped element, these ribs serving to Areinforce this shaped element and as points for the support of a locking mechanism M disposed inside the shaped elements 1 and 2 and serving to lock these shaped elements in the shuttering position shown in FIGS. 2 and 3 by holding a sealing joint between them as will be described in more detail hereafter.

The cross ribs 7 each have inclined edges 7' serving as guiding means for a part of the mechanism M.

The shaped element 2 also has inside cross strengthening ribs 8 serving to support the locking mechanism M and comprising in the centre a projection 9 for centering this mechanism.

A strap 10 fixed on the shaped element 1 (FIGS. S and 6) at one end of the latter supports a U-shaped handle 11, pivoting at 11 on each side of the strap 10. This handle 11 has bent ends 12 each provided with a pin 13 adapted to enter into contact with the corresponding edge of the shaped element 2. By moving the handle 11 from the vertical rest position in dot and dash lines, to the inclined position in full lines, the pins 13 bear against the edges 5 and 6 of the shaped element 2 and the bent ends 12 acting as levers separate the shaped elements 1 and 2 the one from the other.

The locking mechanism M shown in side elevation in FIG. 7 comprises two U-irons 14 and 15, turned back to back and connected together by pairs of links 16 distributed at equal distances along these irons. These links 16 are hinged on spindles 17, '18 passing in bosses 19, 20 integral with the irons 14 and 15 respectively. The iron 14 carries at one end a pivoting lever 21 hinged at 22 to a shorter lever 23 connected to the iron 15. These two levers are held in the full line position -by a spring stop schematized at 24.

The irons 14 and 15 serve to support sealing joints 25 and 26 respectively (FIGS. 1 to 4) adapted to close the free space between the facing edges 3, 5 and 4, 6 respectively of the shaped elements 1 and 2 as shown in FIGS. 2 and 3. These sealing joints 25, 26 are formed by strips of llexible material, for example foam rubber, mounted on elements 27, 28 fixed to the irons 14 and 15.

The core former shown in FIGS. 6 to 8 has an end of reduced section 29 opposite to the one carrying the control handle 11. This end 29 passes through a positioning frame of which one of the sides perpendicular to the axis of the core former is shown in section at 30, and another side parallel to said axis being seen partly at 31. A sealing joint 32 is disposed between the side 30 and the end 29 of reduced section of the device. The positioning frame may receive live core formers such as the one described with a view to producing a construction element having live passages C as shown in FIG. 9. A plate 29 is disposed at the end of the shaped elements 1 and 2 and has for purpose to separate these shaped elements before actuation of the lever 11. The end 29 of reduced section permits of obtaining a larger section in the concrete moulded element, with a view to supporting additional loads.

Instead of a plate 29 one could dispose, for example,

a transverse tube on which would rest the upper shaped element, this tube being removed after actuation of the inner mechanism.

The operation of the core former device described is the following:

To bring the shaped elements 1 and 2 from the position of FIG. 1 to that of FIG. 2, the mechanism M still remaining in the full line position, one moves the handle 11 from the position in dot and dash lines to the position in full lines (FIG. 6). The lever 21 is then actuated from the position in dot and dash lines to that in full lines of FIG. 7 to separate the irons 14 and 15 laterally one from the other, the pairs of links 16 then having the inclined position shown in full lines. During this separating movement, the sealing joints 25 and 26 have been forced between the edges 3, and 4, 6 and at the end of the stroke, the ends of the irons 14 and 15 have come to bear against the supports 3', 5 and 4, 6' respectively of the shaped elements 1 and 2 (FIG. 2).

The concrete is then cast around the core former as shown in FIG. 3. To dismantle the device, one moves the lever 21 into the position in dot and dash lines in FIG. 7, thus bringing back the irons 14 and 15 into their position near to one another as shown in FIG. 4. The shaped element 1 frees itself and cornes to rest on the locking mechanism M. The device may then be withdrawn from the pipe line C to be re-employed.

In the variant of FIGS. and 11, the elements supporting the sealing packing 33 comprise two angle irons 34 and 35 of which one 34 is fixed on a support 36 integral with the iron 14 and the other 35 pivots at 37 on this support 36. In the closed position of the joint (FIG. 10), the element 35 is blocked by the edge 3 of the shaped element 1. When the locking mechanism is loosened and the iron 14 separates from the support 3, the element 35 rocks and disengages the packing 33 of the joint as shown in FIG. 11.

FIG. 12 shows a variant of the locking mechanism M in which one makes use, instead of a working lever, of a screw 38 disposed between a plate 39 integral with the iron 14 and a stop 40 integral with the iron 15. By screwing more or less the nut 41, one separates or one brings nearer in a corresponding manner the irons 14 and 15.

In the variant of FIG. 13, the U-irons 14 and 15 are operated by means of a jack with a deformable parallelogram comprising a threaded rod 42 actuated by a handle 43 to move a tapped sleeve 44 carrying two links 45 connected to the irons 14 and 15. A second pair of sleeves `45 hinged on the one hand tothe irons 14 and 15, and on the other hand, to a stop sleeve 44', held on the threaded rod 42 'by a ring 46, forms the two sides of the deformable parallelogram. Several of these parallelograms may be distributed along the irons 14 and 15.

The core former described has the advantage of being strongly built, rigid and of simple operation, capable of being re-employed at least 2000 times. Due to its rigidity it can stand the pressure of the fresh concrete without necessitating special supporting means. i

It may be dilated by the action of a simple leve after having inserted it in the casting frame without it being necessary to employ a slit mould.

On the other hand, it is possible to produce passages of very large cross section due to the solidity of the former.

What I claim is:

1. A core former for forming a passage in a construction element of hardening material comprising two channel shaped elements turned down one on the other with their longitudinal edges facing each other, means for separating and bringing toward each other said two channel shaped elements in the shuttering or dismantling position, sealing means to close the free space between the longitudinal edges of said channel shaped elements in the shuttering position, said sealing means comprising a locking mechanism having two U-irons turned lback to back and `extending over the whole length of the channel shaped elements, pairs of links connecting said U-irons, operating means to permit movement of the U-irons one relative to the other, a sealing packing integral with each of said irons to close the space between the longitudinal edges of the channel shaped elements, each of said sealing packings being mounted on two similar elements, one of which is xed on an associated U-iron and the other of which is pivoted to said U-iron.

2. A core former according to claim 1 in which the operating means comprises a lever hinged at one end of one of the U-irons and connected to another lever itself hinged at the corresponding end of the other U-iron.

References Cited UNITED STATES PATENTS 142,746 9/ 1873 Smith 249-180 1,000,261 8/1911 Hansen. 1,027,555 5/1912 MacFarlane et al. 1,041,367 10/1912 Steler. 1,060,188 4/1913 Jacobson. 1,112,034 9/1914 Ross. 1,342,208 6/1920 De Zernelmont 249-151 X 2,030,724 2/ 1936 Smith 249-179 X 2,138,693 11/1938 Corwin 249-181 X 2,507,924 5/1950 Morse 249-180 2,819,511 1/1958 Sims 249-181 2,969,575 1/ 1961 Gagne.

FOREIGN PATENTS 240,138 8/ 1962 Australia. 266,424 1927 Great Britain.

J. HOWARD FLINT, IR., Primary Examiner U.S. Cl. X.R. 249-179, 183, 

